package com.henghe.frame.auth.service;

import com.alibaba.fastjson.JSONObject;
import com.henghe.frame.common.util.Base64Decoder;
import com.henghe.frame.core.util.RedisUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Random;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

/**
 * Description:
 * Author: LiuWenQing
 * Datetime: 2023/3/18 08:32
 */
@Service
@Slf4j
public class ValidateCodeService {

    @Autowired
    private RedisUtil redis;

    public static final String RANDOMCODEKEY = "VALIDATECODE";//放到session中的key
    private String randString = "0123456789";//随机产生只有数字的字符串 private String
    //private String randString = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生只有字母的字符串
    //private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生数字与字母组合的字符串
    private int width = 95;// 图片宽
    private int height = 25;// 图片高
    private int lineSize = 5;// 干扰线数量
    private int stringNum = 4;// 随机产生字符数量

    private Random random = new Random();

    public JSONObject generateValidateCode() {
        JSONObject reJo = new JSONObject();
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_BGR);
        Graphics g = image.getGraphics();// 产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
        g.fillRect(0, 0, width, height);//图片大小
        g.setFont(new Font("Times New Roman", Font.ROMAN_BASELINE, 25));//字体大小
        g.setColor(getRandColor(110, 133));//字体颜色
        // 绘制干扰线
        for (int i = 0; i <= lineSize; i++) {
            drowLine(g);
        }
        // 绘制随机字符
        String randomString = "";
        for (int i = 1; i <= stringNum; i++) {
            randomString = drowString(g, randomString, i);
        }
        log.info("生成验证码: {}",randomString);
        g.dispose();
        try {
            //将图片转换陈字符串给前端
            ByteArrayOutputStream stream = new ByteArrayOutputStream();
            ImageIO.write(image, "png", stream);
            String base64 = Base64Decoder.encode(stream.toByteArray());
            reJo.put("image", "data:image/png;base64,"+base64);
            stream.flush();
            stream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        //封装数据
        String uuid = UUID.randomUUID().toString().replace("-", "");
        reJo.put("sessionId", uuid);
        //保存到Redis中sessionId
        redis.put(uuid, randomString, 2 * 60 * 1L, TimeUnit.SECONDS);
        return reJo;
    }

    /**
     * 绘制干扰线
     */
    private void drowLine(Graphics g) {
        int x = random.nextInt(width);
        int y = random.nextInt(height);
        int xl = random.nextInt(13);
        int yl = random.nextInt(15);
        g.drawLine(x, y, x + xl, y + yl);
        g.setColor(new Color(32,67,210));
    }

    /**
     * 获得字体
     */
    private Font getFont() {
        return new Font("Fixedsys", Font.CENTER_BASELINE, 25);
    }

    /**
     * 获得颜色
     */
    private Color getRandColor(int fc, int bc) {
        if (fc > 255)
            fc = 255;
        if (bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc - fc - 16);
        int g = fc + random.nextInt(bc - fc - 14);
        int b = fc + random.nextInt(bc - fc - 18);
        return new Color(r, g, b);
    }

    /**
     * 绘制字符串
     */
    private String drowString(Graphics g, String randomString, int i) {
        g.setFont(getFont());
        g.setColor(new Color(random.nextInt(101), random.nextInt(111), random
                .nextInt(121)));
        String rand = String.valueOf(getRandomString(random.nextInt(randString
                .length())));
        randomString += rand;
        g.translate(random.nextInt(3), random.nextInt(3));
        g.drawString(rand, 13 * i, 16);
        return randomString;
    }

    /**
     * 获取随机的字符
     */
    public String getRandomString(int num) {
        return String.valueOf(randString.charAt(num));
    }
}
